SUMMARY The Animal Models and Pathology Core is established to provide essential animal and pathology resource components that comprehensively support research Projects utilizing animal models. The Specific Aims of this Core are: Specific Aim 1 - To maintain quality controlled breeding colonies for various mouse strains; Specific Aim 2 - To develop novel strains of transgenic mice and maintain breeding colonies of mice that will be specifically utilized by individual Projects in the Program; Specific Aim 3 - To generate mouse embryonic fibroblasts (MEFs) from various mice strains proposed in individual projects; Specific Aim 4 - To provide animal pathology services for in vivo cancer models; and Specific Aim 5 - To provide services for tumor tissue staining and characterization by IHC and TMA.